Exterior Insulation And Finish System (EIFS)

Exterior Insulation And Finish System or EIFS is a “synthetic stucco” product that was designed to replace traditional exterior building materials like portland cement plaster (traditional stucco), siding and masonry veneer. Traditional stucco, siding and masonry veneer systems are designed to manage water penetration through the installation of a secondary weather-resistive barrier, flashing and weeps.

Unlike these traditional systems, barrier-type EIFS does not incorporate the use of a secondary moisture barrier. Instead, it assumes that all water penetration can be prevented at the outer surface. Serious damage arises, however, when water does in fact penetrate the outer barrier. Once the water enters the wall cavity, it cannot escape because the EIFS acts as a barrier to keep the water in the walls. Water trapped in walls that have insulation, wood and drywall creates a primary breeding ground for mold and dry rot. Often, these problems are not seen for years because growth occurs in the walls before it actually gets through the drywall to the interior of the unit.

Can An Exterior Insulation And Finish System Cause More Damage

Newer EIFS uses a drainage “mat” as a secondary barrier to assist in water removal. However, this system can also lead to serious damage. Generally, water entry issues are connected with penetrations such as windows and doors. For both types of EIFS systems, the appropriate flashing and other waterproofing details around windows and doors is critical. If the EIFS (and/or the secondary mat) is improperly installed, excess moisture is trapped in the walls, again causing water damage and mold.